Merge branch 'akpm' (patches from Andrew)

Merge yet more updates from Andrew Morton:

- various misc things

- kexec updates

- sysctl core updates

- scripts/gdb udpates

- checkpoint-restart updates

- ipc updates

- kernel/watchdog updates

- Kees's "rough equivalent to the glibc _FORTIFY_SOURCE=1 feature"

- "stackprotector: ascii armor the stack canary"

- more MM bits

- checkpatch updates

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (96 commits)
  writeback: rework wb_[dec|inc]_stat family of functions
  ARM: samsung: usb-ohci: move inline before return type
  video: fbdev: omap: move inline before return type
  video: fbdev: intelfb: move inline before return type
  USB: serial: safe_serial: move __inline__ before return type
  drivers: tty: serial: move inline before return type
  drivers: s390: move static and inline before return type
  x86/efi: move asmlinkage before return type
  sh: move inline before return type
  MIPS: SMP: move asmlinkage before return type
  m68k: coldfire: move inline before return type
  ia64: sn: pci: move inline before type
  ia64: move inline before return type
  FRV: tlbflush: move asmlinkage before return type
  CRIS: gpio: move inline before return type
  ARM: HP Jornada 7XX: move inline before return type
  ARM: KVM: move asmlinkage before type
  checkpatch: improve the STORAGE_CLASS test
  mm, migration: do not trigger OOM killer when migrating memory
  drm/i915: use __GFP_RETRY_MAYFAIL
  ...

Merge tag 'platform-drivers-x86-v4.13-2' of git://git.infradead.org/linux-platform-drivers-x86

Pull more x86 platform driver updates from Darren Hart:
 "Add new platform matches for silead_dmi and ideapad-laptop. Several
  constify patches for attribute_group structures. Fixes for peaq-wmi
  and intel_telemetry.

  silead_dmi:
   - Add entry for Ployer Momo7w tablet touchscreen
   - Add touchscreen info for I.T.Works TW891 2-in-1

  toshiba_acpi:
   - constify attribute_group structures.

  asus-wmi:
   - constify attribute_group structures.

  panasonic-laptop:
   - constify attribute_group structures.

  alienware-wmi:
   - constify attribute_group structures.

  samsung-laptop:
   - constify attribute_group structures.

  compal-laptop:
   - constify attribute_group structures.

  fujitsu-laptop:
   - constify attribute_group structures.
   - add NULL check on devm_kzalloc() return value

  peaq-wmi:
   - Fix peaq_ignore_events_counter handling off by 1

  ideapad-laptop:
   - Fix indentation in DMI table
   - Add several models to no_hw_rfkill
   - Add IdeaPad V510-15IKB to no_hw_rfkill

  intel_telemetry:
   - Add debugfs entry for S0ix residency

  intel_telemetry_debugfs:
   - fix some error codes in init
   - fix oops when load/unload module"

* tag 'platform-drivers-x86-v4.13-2' of git://git.infradead.org/linux-platform-drivers-x86:
  platform/x86: silead_dmi: Add entry for Ployer Momo7w tablet touchscreen
  platform/x86: toshiba_acpi: constify attribute_group structures.
  platform/x86: asus-wmi: constify attribute_group structures.
  platform/x86: panasonic-laptop: constify attribute_group structures.
  platform/x86: alienware-wmi: constify attribute_group structures.
  platform/x86: samsung-laptop: constify attribute_group structures.
  platform/x86: compal-laptop: constify attribute_group structures.
  platform/x86: fujitsu-laptop: constify attribute_group structures.
  platform/x86: peaq-wmi: Fix peaq_ignore_events_counter handling off by 1
  platform/x86: fujitsu-laptop: add NULL check on devm_kzalloc() return value
  platform/x86: silead_dmi: Add touchscreen info for I.T.Works TW891 2-in-1
  platform/x86: ideapad-laptop: Fix indentation in DMI table
  platform/x86: ideapad-laptop: Add several models to no_hw_rfkill
  platform/x86: ideapad-laptop: Add IdeaPad V510-15IKB to no_hw_rfkill
  platform/x86: intel_telemetry: Add debugfs entry for S0ix residency
  platform/x86: intel_telemetry_debugfs: fix some error codes in init
  platform/x86: intel_telemetry_debugfs: fix oops when load/unload module

Merge tag 'vfio-v4.13-rc1' of git://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - Include Intel XXV710 in INTx workaround (Alex Williamson)

 - Make use of ERR_CAST() for error return (Dan Carpenter)

 - Fix vfio_group release deadlock from iommu notifier (Alex Williamson)

 - Unset KVM-VFIO attributes only on group match (Alex Williamson)

 - Fix release path group/file matching with KVM-VFIO (Alex Williamson)

 - Remove unnecessary lock uses triggering lockdep splat (Alex Williamson)

* tag 'vfio-v4.13-rc1' of git://github.com/awilliam/linux-vfio:
  vfio: Remove unnecessary uses of vfio_container.group_lock
  vfio: New external user group/file match
  kvm-vfio: Decouple only when we match a group
  vfio: Fix group release deadlock
  vfio: Use ERR_CAST() instead of open coding it
  vfio/pci: Add Intel XXV710 to hidden INTx devices

Merge tag 'rtc-4.13' of git://git./linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
 "Here is the pull-request for the RTC subsystem for 4.13.

  Subsystem:

   - expose non volatile RAM using nvmem instead of open coding in many
     drivers. Unfortunately, this option has to be enabled by default to
     not break existing users.

   - rtctest can now test for cutoff dates, showing when an RTC will
     start failing to properly save time and date.

   - new RTC registration functions to remove race conditions in drivers

  Newly supported RTCs:

   - Broadcom STB wake-timer

   - Epson RX8130CE

   - Maxim IC DS1308

   - STMicroelectronics STM32H7

  Drivers:

   - ds1307: use regmap, use nvmem, more cleanups

   - ds3232: temperature reading support

   - gemini: renamed to ftrtc010

   - m41t80: use CCF to expose the clock

   - rv8803: use nvmem

   - s3c: many cleanups

   - st-lpc: fix y2106 bug"

* tag 'rtc-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (51 commits)
  rtc: Remove wrong deprecation comment
  nvmem: include linux/err.h from header
  rtc: st-lpc: make it robust against y2038/2106 bug
  rtc: rtctest: add check for problematic dates
  tools: timer: add rtctest_setdate
  rtc: ds1307: remove ds1307_remove
  rtc: ds1307: use generic nvmem
  rtc: ds1307: switch to rtc_register_device
  rtc: rv8803: remove rv8803_remove
  rtc: rv8803: use generic nvmem support
  rtc: rv8803: switch to rtc_register_device
  rtc: add generic nvmem support
  rtc: at91rm9200: remove race condition
  rtc: introduce new registration method
  rtc: class separate id allocation from registration
  rtc: class separate device allocation from registration
  rtc: stm32: add STM32H7 RTC support
  dt-bindings: rtc: stm32: add support for STM32H7
  rtc: ds1307: add ds1308 variant
  rtc: ds3232: add temperature support
  ...

Merge tag 'for-linus-20170713' of git://git.infradead.org/linux-mtd

Pull MTD updates from Brian Norris:
 "General updates:
   - Cleanups and additional flash support for "dataflash" driver
   - new driver for mchp23k256 SPI SRAM device
   - improve handling of MTDs without eraseblocks (i.e., MTD_NO_ERASE)
   - refactor and improve "sub-partition" handling with TRX partition
     parser; partitions can now be created as sub-partitions of another
     partition

  SPINOR updates, from Cyrille Pitchen and Marek Vasut:
   - introduce support to the SPI 1-2-2 and 1-4-4 protocols.
   - introduce support to the Double Data Rate (DDR) mode.
   - introduce support to the Octo SPI protocols.
   - add support to new memory parts for Spansion, Macronix and Winbond.
   - add fixes for the Aspeed, STM32 and Cadence QSPI controler drivers.
   - clean up the st_spi_fsm driver.

  NAND updates, from Boris Brezillon:
   - addition of on-die ECC support to Micron driver
   - addition of helpers to help drivers choose most appropriate ECC
     settings
   - deletion of dead-code (cached programming and ->errstat() hook)
   - make sure drivers that do not support the SET/GET FEATURES command
     return ENOTSUPP use a dummy ->set/get_features implementation
     returning -ENOTSUPP (required for Micron on-die ECC)
   - change the semantic of ecc->write_page() for drivers setting the
     NAND_ECC_CUSTOM_PAGE_ACCESS flag
   - support exiting 'GET STATUS' command in default ->cmdfunc()
     implementations
   - change the prototype of ->setup_data_interface()

  A bunch of driver related changes:
   - various cleanup, fixes and improvements of the MTK driver
   - OMAP DT bindings fixes
   - support for ->setup_data_interface() in the fsmc driver
   - support for imx7 in the gpmi driver
   - finalization of the denali driver rework (thanks to Masahiro for
     the work he's done on this driver)
   - fix "bitflips in erased pages" handling in the ifc driver
   - addition of PM ops and dynamic timing configuration to the atmel
     driver"

* tag 'for-linus-20170713' of git://git.infradead.org/linux-mtd: (118 commits)
  Documentation: ABI: mtd: describe "offset" more precisely
  mtd: Fix check in mtd_unpoint()
  mtd: nand: mtk: release lock on error path
  mtd: st_spi_fsm: remove SPINOR_OP_RDSR2 and use SPINOR_OP_RDCR instead
  mtd: spi-nor: cqspi: remove duplicate const
  mtd: spi-nor: Add support for Spansion S25FL064L
  mtd: spi-nor: Add support for mx66u51235f
  mtd: nand: mtk: add ->setup_data_interface() hook
  mtd: nand: mtk: remove unneeded mtk_ecc_hw_init from mtk_ecc_resume
  mtd: nand: mtk: remove unneeded mtk_nfc_hw_init from mtk_nfc_resume
  mtd: nand: mtk: disable ecc irq when writing page with hwecc
  mtd: nand: mtk: fix incorrect register setting order about ecc irq
  mtd: partitions: fixup some allocate_partition() whitespace
  mtd: parsers: trx: fix pr_err format for printing offset
  MAINTAINERS: Update SPI NOR subsystem git repositories
  mtd: extract TRX parser out of bcm47xxpart into a separated module
  mtd: partitions: add support for partition parsers
  mtd: partitions: add support for subpartitions
  mtd: partitions: rename "master" to the "parent" where appropriate
  mtd: partitions: remove sysfs files when deleting all master's partitions
  ...

Merge tag 'fbdev-v4.13' of git://github.com/bzolnier/linux

Pull fbdev updates from Bartlomiej Zolnierkiewicz:
 "There is nothing really major here, just a couple of small bugfixes,
  improvements and cleanups.

   - fix get_fb_unmapped_area() helper handling (Benjamin Gaignard)

   - check return value of clk_prepare_enable() in pxafb driver (Arvind
     Yadav)

   - fix error path handling in vmlfb driver (Alexey Khoroshilov)

   - printks fixes/cleanups for uvesafb driver (Joe Perches)

   - fix unusued variable warning in atyfb driver (Arnd Bergmann)

   - constifications for sh_mobile_lcdcfb, fsl-diu-fb, omapfb (Arvind
     Yadav)

   - mdacon driver cleanups (Jiri Slaby)

   - misc cleanups (Andy Shevchenko, Karim Eshapa, Gustavo A. R. Silva,
     Dan Carpenter)"

* tag 'fbdev-v4.13' of git://github.com/bzolnier/linux:
  fbdev: make get_fb_unmapped_area depends of !MMU
  atyfb: hide unused variable
  video: fbdev: matrox: the list iterator can't be NULL
  video: fbdev: aty: remove useless variable assignments in aty_var_to_crtc()
  fbdev: omapfb: constify ctrl_caps, color_caps, panel_attr_grp and ctrl_attr_grp
  omapfb: panel-dsi-cm: constify dsicm_attr_group
  vmlfb: Fix error handling in cr_pll_init()
  video: fbdev: fsl-diu-fb: constify mfb_template and fsl_diu_match.
  uvesafb: Fix continuation printks without KERN_LEVEL to pr_cont, neatening
  video: fbdev: sh_mobile_lcdcfb: constify sh_mobile_lcdc_bl_ops.
  omapfb: Use sysfs_match_string() helper
  video: fbdev: pxafb: Handle return value of clk_prepare_enable
  video: fbdev: omap2: omapfb: displays: panel-dsi-cm: Use time comparison kernel macro.
  mdacon: replace MDA_ADDR macro by inline function
  mdacon: make mda_vram_base u16 *
  mdacon: align code in mda_detect properly

Merge tag 'pwm/for-4.13-rc1' of git://git./linux/kernel/git/thierry.reding/linux-pwm

Pull pwm updates from Thierry Reding:
 "This release cycle's changes include mostly updates and cleanups to
  existing drivers along with a few cleanups to the core, documentation
  and device tree bindings"

* tag 'pwm/for-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm:
  pwm: cros-ec: Fix transposed param settings
  pwm: meson: Improve PWM calculation precision
  dt-bindings: pwm: meson: Add compatible for gxbb ao PWMs
  pwm: meson: Add compatible for the gxbb ao PWMs
  pwm: sun4i: Drop legacy callbacks
  pwm: sun4i: Switch to atomic PWM
  pwm: sun4i: Improve hardware read out
  pwm: hibvt: Constify hibvt_pwm_ops
  pwm: Silently error out on EPROBE_DEFER
  pwm: Standardize document format
  pwm: bfin: Remove unneeded error message
  dt-bindings: pwm: Update STM32 timers clock names
  dt-bindings: pwm: Add R-Car M3-W device tree bindings
  pwm: tegra: Set maximum pwm clock source per SoC tapeout

Merge tag 'for-v4.13-2' of git://git./linux/kernel/git/sre/linux-power-supply

Pull power supply fixes from  Reichel:
 "I have two more fixes for the power-supply subsystem:

   - two fixes for twl4030-charger"

* tag 'for-v4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply:
  power: supply: twl4030-charger: add deferred probing for phy and iio
  power: supply: twl4030-charger: move irq allocation to just before irqs are enabled

Merge tag 'drm-fixes-for-v4.13-rc1' of git://people.freedesktop.org/~airlied/linux

Pull more drm updates from Dave Airlie:
 "i915, amd and some core fixes + mediatek color support.

  Some fixes tree came in since the main pull request for rc1, primarily
  i915 and drm-misc and one amd fix. The drm core vblank regression fix
  is probably the most important thing.

  I've also added the mediatek feature pull, it wasn't that big and
  didn't look like it would have any impact outside of mediatek, in fact
  it looks to just be a single feature, and some cleanups"

* tag 'drm-fixes-for-v4.13-rc1' of git://people.freedesktop.org/~airlied/linux: (31 commits)
  drm/i915: Make DP-MST connector info work
  drm/i915/gvt: Use fence error from GVT request for workload status
  drm/i915/gvt: remove scheduler_mutex in per-engine workload_thread
  drm/i915/gvt: Revert "drm/i915/gvt: Fix possible recursive locking issue"
  drm/i915/gvt: Audit the command buffer address
  drm/i915/gvt: Fix a memory leak in intel_gvt_init_gtt()
  drm/rockchip: fix NULL check on devm_kzalloc() return value
  drm/i915/fbdev: Check for existence of ifbdev->vma before operations
  drm/radeon: Fix eDP for single-display iMac10,1 (v2)
  drm/i915: Hold RPM wakelock while initializing OA buffer
  drm/i915/cnl: Fix the CURSOR_COEFF_MASK used in DDI Vswing Programming
  drm/i915/cfl: Fix Workarounds.
  drm/i915: Avoid undefined behaviour of "u32 >> 32"
  drm/i915: reintroduce VLV/CHV PFI programming power domain workaround
  drm/i915: Fix an error checking test
  drm/i915: Disable MSI for all pre-gen5
  drm/atomic: Add missing drm_atomic_state_clear to atomic_remove_fb
  drm: vblank: Fix vblank timestamp update
  drm/i915/gvt: Make function dpy_reg_mmio_readx safe
  drm/mediatek: separate color module to fixup error memory reallocation
  ...

drm: Add missing field copy in compat_drm_version

DRM_IOCTL_VERSION is supposed to update the name_len/date_len/desc_len
fields to user.

Fixes: 012c6741c6aa ("switch compat_drm_version() to drm_ioctl_kernel()")
Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Documentation: ABI: mtd: describe "offset" more precisely

So far Linux supported only two levels of MTD devices so we didn't need
a very precise description for this sysfs file. With commit
97519dc52b44a ("mtd: partitions: add support for subpartitions") there
is support for a tree structure so we should have more precise
description. Using "parent" and "flash device" makes it more accurate.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

Merge branch 'drm-next-4.13' of git://people.freedesktop.org/~agd5f/linux into drm-next

single r700 fix.
* 'drm-next-4.13' of git://people.freedesktop.org/~agd5f/linux:
  drm/radeon: Fix eDP for single-display iMac10,1 (v2)

Merge branch 'for-linus' of git://git./linux/kernel/git/ebiederm/user-namespace

Pull sysctl fix from Eric Biederman:
 "A rather embarassing and hard to hit bug was merged into 4.11-rc1.

  Andrei Vagin tracked this bug now and after some staring at the code
  I came up with a fix"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  proc: Fix proc_sys_prune_dcache to hold a sb reference

Merge git://git./linux/kernel/git/davem/net

Pull networking fixes from David Miller:

1) Fix 64-bit division in mlx5 IPSEC offload support, from Ilan Tayari
   and Arnd Bergmann.

2) Fix race in statistics gathering in bnxt_en driver, from Michael
   Chan.

3) Can't use a mutex in RCU reader protected section on tap driver, from
   Cong WANG.

4) Fix mdb leak in bridging code, from Eduardo Valentin.

5) Fix free of wrong pointer variable in nfp driver, from Dan Carpenter.

6) Buffer overflow in brcmfmac driver, from Arend van SPriel.

7) ioremap_nocache() return value needs to be checked in smsc911x
   driver, from Alexey Khoroshilov.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (34 commits)
  net: stmmac: revert "support future possible different internal phy mode"
  sfc: don't read beyond unicast address list
  datagram: fix kernel-doc comments
  socket: add documentation for missing elements
  smsc911x: Add check for ioremap_nocache() return code
  brcmfmac: fix possible buffer overflow in brcmf_cfg80211_mgmt_tx()
  net: hns: Bugfix for Tx timeout handling in hns driver
  net: ipmr: ipmr_get_table() returns NULL
  nfp: freeing the wrong variable
  mlxsw: spectrum_switchdev: Check status of memory allocation
  mlxsw: spectrum_switchdev: Remove unused variable
  mlxsw: spectrum_router: Fix use-after-free in route replace
  mlxsw: spectrum_router: Add missing rollback
  samples/bpf: fix a build issue
  bridge: mdb: fix leak on complete_info ptr on fail path
  tap: convert a mutex to a spinlock
  cxgb4: fix BUG() on interrupt deallocating path of ULD
  qed: Fix printk option passed when printing ipv6 addresses
  net: Fix minor code bug in timestamping.txt
  net: stmmac: Make 'alloc_dma_[rt]x_desc_resources()' look even closer
  ...

disable new gcc-7.1.1 warnings for now

I made the mistake of upgrading my desktop to the new Fedora 26 that
comes with gcc-7.1.1.

There's nothing wrong per se that I've noticed, but I now have 1500
lines of warnings, mostly from the new format-truncation warning
triggering all over the tree.

We use 'snprintf()' and friends in a lot of places, and often know that
the numbers are fairly small (ie a controller index or similar), but gcc
doesn't know that, and sees an 'int', and thinks that it could be some
huge number.  And then complains when our buffers are not able to fit
the name for the ten millionth controller.

These warnings aren't necessarily bad per se, and we probably want to
look through them subsystem by subsystem, but at least during the merge
window they just mean that I can't even see if somebody is introducing
any *real* problems when I pull.

So warnings disabled for now.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'drm-misc-next-fixes-2017-07-10' of git://anongit.freedesktop.org/git/drm-misc into drm-next

Core Changes:
- Fix empty timestamps on hw without vlbank counter (Laurent)
- Clear atomic state before retrying ww/mutex acquisition in remove_fb (Maarten)

Driver Changes:
- rockchip: Fix incorrect NULL pointer check after allocation (Gustavo)

Cc: Gustavo A. R. Silva <garsilva@embeddedor.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
* tag 'drm-misc-next-fixes-2017-07-10' of git://anongit.freedesktop.org/git/drm-misc:
  drm/rockchip: fix NULL check on devm_kzalloc() return value
  drm/atomic: Add missing drm_atomic_state_clear to atomic_remove_fb
  drm: vblank: Fix vblank timestamp update
  DRM: Fix an incorrectly formatted table
  bridge: Fix panel-bridge error return on !panel.
  drm/rockchip: gem: add the lacks lock and trivial changes

Merge tag 'drm-intel-next-fixes-2017-07-11' of git://anongit.freedesktop.org/git/drm-intel into drm-next

drm/i915 fixes for v4.13-rc1

* tag 'drm-intel-next-fixes-2017-07-11' of git://anongit.freedesktop.org/git/drm-intel:
  drm/i915: Make DP-MST connector info work
  drm/i915/gvt: Use fence error from GVT request for workload status
  drm/i915/gvt: remove scheduler_mutex in per-engine workload_thread
  drm/i915/gvt: Revert "drm/i915/gvt: Fix possible recursive locking issue"
  drm/i915/gvt: Audit the command buffer address
  drm/i915/gvt: Fix a memory leak in intel_gvt_init_gtt()
  drm/i915/fbdev: Check for existence of ifbdev->vma before operations
  drm/i915: Hold RPM wakelock while initializing OA buffer
  drm/i915/cnl: Fix the CURSOR_COEFF_MASK used in DDI Vswing Programming
  drm/i915/cfl: Fix Workarounds.
  drm/i915: Avoid undefined behaviour of "u32 >> 32"
  drm/i915: reintroduce VLV/CHV PFI programming power domain workaround
  drm/i915: Fix an error checking test
  drm/i915: Disable MSI for all pre-gen5
  drm/i915/gvt: Make function dpy_reg_mmio_readx safe
  drm/i915/gvt: Don't read ADPA_CRT_HOTPLUG_MONITOR from host
  drm/i915/gvt: Set initial PORT_CLK_SEL vreg for BDW
  drm/i915/gvt: Fix inconsistent locks holding sequence
  drm/i915/gvt: Fix possible recursive locking issue

Merge branch 'mediatek-drm-next-4.13' of https://github.com/ckhu-mediatek/linux.git-tags into drm-next

This include new color format support and some fixups.

* 'mediatek-drm-next-4.13' of https://github.com/ckhu-mediatek/linux.git-tags:
  drm/mediatek: separate color module to fixup error memory reallocation
  drm/mediatek: check for memory allocation failure
  drm/mediatek: re-phrase DRM_INFO error message
  drm/mediatek: use platform_register_drivers
  drm/mediatek: Support UYVY and YUYV format for overlay

Merge tag 'modules-for-v4.13' of git://git./linux/kernel/git/jeyu/linux

Pull modules updates from Jessica Yu:
 "Summary of modules changes for the 4.13 merge window:

   - Minor code cleanups

   - Avoid accessing mod struct prior to checking module struct version,
     from Kees

   - Fix racy atomic inc/dec logic of kmod_concurrent_max in kmod, from
     Luis"

* tag 'modules-for-v4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  module: make the modinfo name const
  kmod: reduce atomic operations on kmod_concurrent and simplify
  module: use list_for_each_entry_rcu() on find_module_all()
  kernel/module.c: suppress warning about unused nowarn variable
  module: Add module name to modinfo
  module: Pass struct load_info into symbol checks

writeback: rework wb_[dec|inc]_stat family of functions

Currently the writeback statistics code uses a percpu counters to hold
various statistics.  Furthermore we have 2 families of functions - those
which disable local irq and those which doesn't and whose names begin
with double underscore.  However, they both end up calling
__add_wb_stats which in turn calls percpu_counter_add_batch which is
already irq-safe.

Exploiting this fact allows to eliminated the __wb_* functions since
they don't add any further protection than we already have.
Furthermore, refactor the wb_* function to call __add_wb_stat directly
without the irq-disabling dance.  This will likely result in better
runtime of code which deals with modifying the stat counters.

While at it also document why percpu_counter_add_batch is in fact
preempt and irq-safe since at least 3 people got confused.

Link: http://lkml.kernel.org/r/1498029937-27293-1-git-send-email-nborisov@suse.com
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ARM: samsung: usb-ohci: move inline before return type

Make the code like the rest of the kernel.

Link: http://lkml.kernel.org/r/667a515b8d0f10f2465d519f8595edd91552fc5e.1499284835.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

video: fbdev: omap: move inline before return type

Make the code like the rest of the kernel.

Link: http://lkml.kernel.org/r/bc5927726abc70d7c066df7ab4cb7cfce4a7b577.1499284835.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

video: fbdev: intelfb: move inline before return type

Make the code like the rest of the kernel.

But there is an oddity here because the inline should probably be removed.

It's an extern function in intelfb.h and it is used in intelfbdrv.c and
intelfbhw.c.

The inline is kept here as I suppose it's possible for some compiler to
make the uses inline in intelfbdrv and and also create an external
function for intelfbhw.

Link: http://lkml.kernel.org/r/8ba151a1fdc84e42cbf4aafc798513c0158edee1.1499284835.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Maik Broemme <mbroemme@libmpq.org>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

USB: serial: safe_serial: move __inline__ before return type

Make the code like the rest of the kernel.
Also use inline instead of __inline__.

Link: http://lkml.kernel.org/r/a5072b74b6c293e6ec93c4900482e9d3267f15b2.1499284835.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Johan Hovold <johan@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers: tty: serial: move inline before return type

Make the code like the rest of the kernel.

Link: http://lkml.kernel.org/r/55d3e89d50bb03d603bfb28019fab07f48bdc714.1499284835.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Pat Gefre <pfg@sgi.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers: s390: move static and inline before return type

Make the code like the rest of the kernel.

Link: http://lkml.kernel.org/r/3f980cd89084ae09716353aba3171e4b3815e690.1499284835.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Cc: Ursula Braun <ubraun@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

x86/efi: move asmlinkage before return type

Make the code like the rest of the kernel.

Link: http://lkml.kernel.org/r/1cd3d401626e51ea0e2333a860e76e80bc560a4c.1499284835.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

sh: move inline before return type

Make the code like the rest of the kernel.

Link: http://lkml.kernel.org/r/f81bb2a67a97b1fd8b6ea99bd350d8a0f6864fb1.1499284835.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MIPS: SMP: move asmlinkage before return type

Make the code like the rest of the kernel.

Link: http://lkml.kernel.org/r/756d3fb543e981b9284e756fa27616725a354b28.1499284835.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

m68k: coldfire: move inline before return type

Make the code like the rest of the kernel.

Link: http://lkml.kernel.org/r/14db9c166d5b68efa77e337cfe49bb9b29bca3f7.1499284835.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Greg Ungerer <gerg@linux-m68k.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ia64: sn: pci: move inline before type

Make the use of inline like the rest of the kernel.

Link: http://lkml.kernel.org/r/f42b2202bd0d4e7ccf79ce5348bb255a035e67bb.1499284835.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ia64: move inline before return type

Make the use of inline like the rest of the kernel.

Link: http://lkml.kernel.org/r/d47074493af80ce12590340294bc49618165c30d.1499284835.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

FRV: tlbflush: move asmlinkage before return type

Make the use of asmlinkage like the rest of the kernel.

Link: http://lkml.kernel.org/r/efb2dfed4d9315bf68ec0334c81b65af176a0174.1499284835.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

CRIS: gpio: move inline before return type

Move inline to be like the rest of the kernel.

Link: http://lkml.kernel.org/r/6bf1bec049897c4158f698b866810f47c728f233.1499284835.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ARM: HP Jornada 7XX: move inline before return type

Convert 'u8 inline' to 'inline u8' to be the same style used by the rest
of the kernel.

Miscellanea:

jornada_ssp_reverse is an odd function.
It is declared inline but is also EXPORT_SYMBOL.
It is also apparently only used by jornada720_ssp.c
Likely the EXPORT_SYMBOL could be removed and the function
converted to static.

The addition of static and removal of EXPORT_SYMBOL was not done.

Link: http://lkml.kernel.org/r/5bd3b2bf39c6c9caf773949f18158f8f5ec08582.1499284835.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ARM: KVM: move asmlinkage before type

asmlinkage is either 'extern "C"' or blank.

Move the uses of asmlinkage before the return types to be similar
to the rest of the kernel.

Link: http://lkml.kernel.org/r/005b8e120650c6a13b541e420f4e3605603fe9e6.1499284835.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: improve the STORAGE_CLASS test

Make sure static, extern, and asmlinkage appear before a specific type.

e.g.:
int asmlinkage foo(void)
is better written
       asmlinkage int foo(void)

Link: http://lkml.kernel.org/r/31704c96df2d5fd9df0b41165940a7a4feb16a63.1499284835.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm, migration: do not trigger OOM killer when migrating memory

Page migration (for memory hotplug, soft_offline_page or mbind) needs to
allocate a new memory.  This can trigger an oom killer if the target
memory is depleated.  Although quite unlikely, still possible,
especially for the memory hotplug (offlining of memoery).

Up to now we didn't really have reasonable means to back off.
__GFP_NORETRY can fail just too easily and __GFP_THISNODE sticks to a
single node and that is not suitable for all callers.

But now that we have __GFP_RETRY_MAYFAIL we should use it.  It is
preferable to fail the migration than disrupt the system by killing some
processes.

Link: http://lkml.kernel.org/r/20170623085345.11304-7-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Alex Belits <alex.belits@cavium.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: NeilBrown <neilb@suse.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drm/i915: use __GFP_RETRY_MAYFAIL

Commit 24f8e00a8a2e ("drm/i915: Prefer to report ENOMEM rather than
incur the oom for gfx allocations") has tried to remove disruptive OOM
killer because the userspace should be able to cope with allocation
failures.

At the time only __GFP_NORETRY could achieve that and it turned out that
this would fail the allocations just too easily.  So "drm/i915: Remove
__GFP_NORETRY from our buffer allocator" removed it and hoped for a
better solution.  __GFP_RETRY_MAYFAIL is that solution.  It will keep
retrying the allocation until there is no more progress and we would go
OOM.  Instead we fail the allocation and let the caller to deal with it.

Link: http://lkml.kernel.org/r/20170623085345.11304-6-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Alex Belits <alex.belits@cavium.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: NeilBrown <neilb@suse.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm: kvmalloc support __GFP_RETRY_MAYFAIL for all sizes

Now that __GFP_RETRY_MAYFAIL has a reasonable semantic regardless of the
request size we can drop the hackish implementation for !costly orders.
__GFP_RETRY_MAYFAIL retries as long as the reclaim makes a forward
progress and backs of when we are out of memory for the requested size.
Therefore we do not need to enforce__GFP_NORETRY for !costly orders just
to silent the oom killer anymore.

Link: http://lkml.kernel.org/r/20170623085345.11304-5-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Alex Belits <alex.belits@cavium.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: NeilBrown <neilb@suse.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

xfs: map KM_MAYFAIL to __GFP_RETRY_MAYFAIL

KM_MAYFAIL didn't have any suitable GFP_FOO counterpart until recently
so it relied on the default page allocator behavior for the given set of
flags.  This means that small allocations actually never failed.

Now that we have __GFP_RETRY_MAYFAIL flag which works independently on
the allocation request size we can map KM_MAYFAIL to it.  The allocator
will try as hard as it can to fulfill the request but fails eventually
if the progress cannot be made.  It does so without triggering the OOM
killer which can be seen as an improvement because KM_MAYFAIL users
should be able to deal with allocation failures.

Link: http://lkml.kernel.org/r/20170623085345.11304-4-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Alex Belits <alex.belits@cavium.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: David Daney <david.daney@cavium.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: NeilBrown <neilb@suse.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm, tree wide: replace __GFP_REPEAT by __GFP_RETRY_MAYFAIL with more useful semantic

__GFP_REPEAT was designed to allow retry-but-eventually-fail semantic to
the page allocator.  This has been true but only for allocations
requests larger than PAGE_ALLOC_COSTLY_ORDER.  It has been always
ignored for smaller sizes.  This is a bit unfortunate because there is
no way to express the same semantic for those requests and they are
considered too important to fail so they might end up looping in the
page allocator for ever, similarly to GFP_NOFAIL requests.

Now that the whole tree has been cleaned up and accidental or misled
usage of __GFP_REPEAT flag has been removed for !costly requests we can
give the original flag a better name and more importantly a more useful
semantic.  Let's rename it to __GFP_RETRY_MAYFAIL which tells the user
that the allocator would try really hard but there is no promise of a
success.  This will work independent of the order and overrides the
default allocator behavior.  Page allocator users have several levels of
guarantee vs.  cost options (take GFP_KERNEL as an example)

 - GFP_KERNEL & ~__GFP_RECLAIM - optimistic allocation without _any_
   attempt to free memory at all. The most light weight mode which even
   doesn't kick the background reclaim. Should be used carefully because
   it might deplete the memory and the next user might hit the more
   aggressive reclaim

 - GFP_KERNEL & ~__GFP_DIRECT_RECLAIM (or GFP_NOWAIT)- optimistic
   allocation without any attempt to free memory from the current
   context but can wake kswapd to reclaim memory if the zone is below
   the low watermark. Can be used from either atomic contexts or when
   the request is a performance optimization and there is another
   fallback for a slow path.

 - (GFP_KERNEL|__GFP_HIGH) & ~__GFP_DIRECT_RECLAIM (aka GFP_ATOMIC) -
   non sleeping allocation with an expensive fallback so it can access
   some portion of memory reserves. Usually used from interrupt/bh
   context with an expensive slow path fallback.

 - GFP_KERNEL - both background and direct reclaim are allowed and the
   _default_ page allocator behavior is used. That means that !costly
   allocation requests are basically nofail but there is no guarantee of
   that behavior so failures have to be checked properly by callers
   (e.g. OOM killer victim is allowed to fail currently).

 - GFP_KERNEL | __GFP_NORETRY - overrides the default allocator behavior
   and all allocation requests fail early rather than cause disruptive
   reclaim (one round of reclaim in this implementation). The OOM killer
   is not invoked.

 - GFP_KERNEL | __GFP_RETRY_MAYFAIL - overrides the default allocator
   behavior and all allocation requests try really hard. The request
   will fail if the reclaim cannot make any progress. The OOM killer
   won't be triggered.

 - GFP_KERNEL | __GFP_NOFAIL - overrides the default allocator behavior
   and all allocation requests will loop endlessly until they succeed.
   This might be really dangerous especially for larger orders.

Existing users of __GFP_REPEAT are changed to __GFP_RETRY_MAYFAIL
because they already had their semantic.  No new users are added.
__alloc_pages_slowpath is changed to bail out for __GFP_RETRY_MAYFAIL if
there is no progress and we have already passed the OOM point.

This means that all the reclaim opportunities have been exhausted except
the most disruptive one (the OOM killer) and a user defined fallback
behavior is more sensible than keep retrying in the page allocator.

[akpm@linux-foundation.org: fix arch/sparc/kernel/mdesc.c]
[mhocko@suse.com: semantic fix]
Link: http://lkml.kernel.org/r/20170626123847.GM11534@dhcp22.suse.cz
[mhocko@kernel.org: address other thing spotted by Vlastimil]
Link: http://lkml.kernel.org/r/20170626124233.GN11534@dhcp22.suse.cz
Link: http://lkml.kernel.org/r/20170623085345.11304-3-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Alex Belits <alex.belits@cavium.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: NeilBrown <neilb@suse.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MIPS: do not use __GFP_REPEAT for order-0 request

Patch series "mm: give __GFP_REPEAT a better semantic".

The main motivation for the change is that the current implementation of
__GFP_REPEAT is not very much useful.

The documentation says:
 * __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt
 *   _might_ fail.  This depends upon the particular VM implementation.

It just fails to mention that this is true only for large (costly) high
order which has been the case since the flag was introduced.  A similar
semantic would be really helpful for smal orders as well, though,
because we have places where a failure with a specific fallback error
handling is preferred to a potential endless loop inside the page
allocator.

The earlier cleanup dropped __GFP_REPEAT usage for low (!costly) order
users so only those which might use larger orders have stayed.  One new
user added in the meantime is addressed in patch 1.

Let's rename the flag to something more verbose and use it for existing
users.  Semantic for those will not change.  Then implement low
(!costly) orders failure path which is hit after the page allocator is
about to invoke the oom killer.  With that we have a good counterpart
for __GFP_NORETRY and finally can tell try as hard as possible without
the OOM killer.

Xfs code already has an existing annotation for allocations which are
allowed to fail and we can trivially map them to the new gfp flag
because it will provide the semantic KM_MAYFAIL wants.  Christoph didn't
consider the new flag really necessary but didn't respond to the OOM
killer aspect of the change so I have kept the patch.  If this is still
seen as not really needed I can drop the patch.

kvmalloc will allow also !costly high order allocations to retry hard
before falling back to the vmalloc.

drm/i915 asked for the new semantic explicitly.

Memory migration code, especially for the memory hotplug, should back
off rather than invoking the OOM killer as well.

This patch (of 6):

Commit 3377e227af44 ("MIPS: Add 48-bit VA space (and 4-level page
tables) for 4K pages.") has added a new __GFP_REPEAT user but using this
flag doesn't really make any sense for order-0 request which is the case
here because PUD_ORDER is 0.  __GFP_REPEAT has historically effect only
on allocation requests with order > PAGE_ALLOC_COSTLY_ORDER.

This doesn't introduce any functional change.  This is a preparatory
patch for later work which renames the flag and redefines its semantic.

Link: http://lkml.kernel.org/r/20170623085345.11304-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Alex Belits <alex.belits@cavium.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: NeilBrown <neilb@suse.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

powerpc,mmap: properly account for stack randomization in mmap_base

When RLIMIT_STACK is, for example, 256MB, the current code results in a
gap between the top of the task and mmap_base of 256MB, failing to take
into account the amount by which the stack address was randomized.  In
other words, the stack gets less than RLIMIT_STACK space.

Ensure that the gap between the stack and mmap_base always takes stack
randomization and the stack guard gap into account.

Inspired by Daniel Micay's linux-hardened tree.

Link: http://lkml.kernel.org/r/20170622200033.25714-4-riel@redhat.com
Signed-off-by: Rik van Riel <riel@redhat.com>
Reported-by: Florian Weimer <fweimer@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Daniel Micay <danielmicay@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arm64/mmap: properly account for stack randomization in mmap_base

When RLIMIT_STACK is, for example, 256MB, the current code results in a
gap between the top of the task and mmap_base of 256MB, failing to take
into account the amount by which the stack address was randomized.  In
other words, the stack gets less than RLIMIT_STACK space.

Ensure that the gap between the stack and mmap_base always takes stack
randomization and the stack guard gap into account.

Obtained from Daniel Micay's linux-hardened tree.

Link: http://lkml.kernel.org/r/20170622200033.25714-3-riel@redhat.com
Signed-off-by: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Rik van Riel <riel@redhat.com>
Reported-by: Florian Weimer <fweimer@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Daniel Micay <danielmicay@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

x86/mmap: properly account for stack randomization in mmap_base

When RLIMIT_STACK is, for example, 256MB, the current code results in a
gap between the top of the task and mmap_base of 256MB, failing to take
into account the amount by which the stack address was randomized.  In
other words, the stack gets less than RLIMIT_STACK space.

Ensure that the gap between the stack and mmap_base always takes stack
randomization and the stack guard gap into account.

Obtained from Daniel Micay's linux-hardened tree.

Link: http://lkml.kernel.org/r/20170622200033.25714-2-riel@redhat.com
Signed-off-by: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Rik van Riel <riel@redhat.com>
Reported-by: Florian Weimer <fweimer@redhat.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Daniel Micay <danielmicay@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

sh64: ascii armor the sh64 boot init stack canary

Use the ascii-armor canary to prevent unterminated C string overflows
from being able to successfully overwrite the canary, even if they
somehow obtain the canary value.

Inspired by execshield ascii-armor and Daniel Micay's linux-hardened
tree.

Link: http://lkml.kernel.org/r/20170524123446.78510066@annuminas.surriel.com
Signed-off-by: Rik van Riel <riel@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Daniel Micay <danielmicay@gmail.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arm64: ascii armor the arm64 boot init stack canary

Use the ascii-armor canary to prevent unterminated C string overflows
from being able to successfully overwrite the canary, even if they
somehow obtain the canary value.

Inspired by execshield ascii-armor and Daniel Micay's linux-hardened
tree.

Link: http://lkml.kernel.org/r/20170524155751.424-5-riel@redhat.com
Signed-off-by: Rik van Riel <riel@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Daniel Micay <danielmicay@gmail.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

x86: ascii armor the x86_64 boot init stack canary

Use the ascii-armor canary to prevent unterminated C string overflows
from being able to successfully overwrite the canary, even if they
somehow obtain the canary value.

Inspired by execshield ascii-armor and Daniel Micay's linux-hardened
tree.

Link: http://lkml.kernel.org/r/20170524155751.424-4-riel@redhat.com
Signed-off-by: Rik van Riel <riel@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Daniel Micay <danielmicay@gmail.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fork,random: use get_random_canary() to set tsk->stack_canary

Use the ascii-armor canary to prevent unterminated C string overflows
from being able to successfully overwrite the canary, even if they
somehow obtain the canary value.

Inspired by execshield ascii-armor and Daniel Micay's linux-hardened
tree.

Link: http://lkml.kernel.org/r/20170524155751.424-3-riel@redhat.com
Signed-off-by: Rik van Riel <riel@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Daniel Micay <danielmicay@gmail.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

random,stackprotect: introduce get_random_canary function

Patch series "stackprotector: ascii armor the stack canary", v2.

Zero out the first byte of the stack canary value on 64 bit systems, in
order to mitigate unterminated C string overflows.

The null byte both prevents C string functions from reading the canary,
and from writing it if the canary value were guessed or obtained through
some other means.

Reducing the entropy by 8 bits is acceptable on 64-bit systems, which
will still have 56 bits of entropy left, but not on 32 bit systems, so
the "ascii armor" canary is only implemented on 64-bit systems.

Inspired by the "ascii armor" code in execshield and Daniel Micay's
linux-hardened tree.

Also see https://github.com/thestinger/linux-hardened/

This patch (of 5):

Introduce get_random_canary(), which provides a random unsigned long
canary value with the first byte zeroed out on 64 bit architectures, in
order to mitigate non-terminated C string overflows.

The null byte both prevents C string functions from reading the canary,
and from writing it if the canary value were guessed or obtained through
some other means.

Reducing the entropy by 8 bits is acceptable on 64-bit systems, which
will still have 56 bits of entropy left, but not on 32 bit systems, so
the "ascii armor" canary is only implemented on 64-bit systems.

Inspired by the "ascii armor" code in the old execshield patches, and
Daniel Micay's linux-hardened tree.

Link: http://lkml.kernel.org/r/20170524155751.424-2-riel@redhat.com
Signed-off-by: Rik van Riel <riel@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Daniel Micay <danielmicay@gmail.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

sh: mark end of BUG() implementation as unreachable

When building the sh architecture, the compiler doesn't realize that
BUG() doesn't return, so it will complain about functions using BUG()
that are marked with the noreturn attribute:

   lib/string.c: In function 'fortify_panic':
>> lib/string.c:986:1: warning: 'noreturn' function does return
    }
    ^

Link: http://lkml.kernel.org/r/20170627192050.GA66784@beast
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/string.h: add the option of fortified string.h functions

This adds support for compiling with a rough equivalent to the glibc
_FORTIFY_SOURCE=1 feature, providing compile-time and runtime buffer
overflow checks for string.h functions when the compiler determines the
size of the source or destination buffer at compile-time.  Unlike glibc,
it covers buffer reads in addition to writes.

GNU C __builtin_*_chk intrinsics are avoided because they would force a
much more complex implementation.  They aren't designed to detect read
overflows and offer no real benefit when using an implementation based
on inline checks.  Inline checks don't add up to much code size and
allow full use of the regular string intrinsics while avoiding the need
for a bunch of _chk functions and per-arch assembly to avoid wrapper
overhead.

This detects various overflows at compile-time in various drivers and
some non-x86 core kernel code.  There will likely be issues caught in
regular use at runtime too.

Future improvements left out of initial implementation for simplicity,
as it's all quite optional and can be done incrementally:

* Some of the fortified string functions (strncpy, strcat), don't yet
  place a limit on reads from the source based on __builtin_object_size of
  the source buffer.

* Extending coverage to more string functions like strlcat.

* It should be possible to optionally use __builtin_object_size(x, 1) for
  some functions (C strings) to detect intra-object overflows (like
  glibc's _FORTIFY_SOURCE=2), but for now this takes the conservative
  approach to avoid likely compatibility issues.

* The compile-time checks should be made available via a separate config
  option which can be enabled by default (or always enabled) once enough
  time has passed to get the issues it catches fixed.

Kees said:
 "This is great to have. While it was out-of-tree code, it would have
  blocked at least CVE-2016-3858 from being exploitable (improper size
  argument to strlcpy()). I've sent a number of fixes for
  out-of-bounds-reads that this detected upstream already"

[arnd@arndb.de: x86: fix fortified memcpy]
Link: http://lkml.kernel.org/r/20170627150047.660360-1-arnd@arndb.de
[keescook@chromium.org: avoid panic() in favor of BUG()]
Link: http://lkml.kernel.org/r/20170626235122.GA25261@beast
[keescook@chromium.org: move from -mm, add ARCH_HAS_FORTIFY_SOURCE, tweak Kconfig help]
Link: http://lkml.kernel.org/r/20170526095404.20439-1-danielmicay@gmail.com
Link: http://lkml.kernel.org/r/1497903987-21002-8-git-send-email-keescook@chromium.org
Signed-off-by: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

powerpc: make feature-fixup tests fortify-safe

Testing the fortified string functions[1] would cause a kernel panic on
boot in test_feature_fixups() due to a buffer overflow in memcmp.

This boils down to things like this:

  extern unsigned int ftr_fixup_test1;
  extern unsigned int ftr_fixup_test1_orig;

  check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_orig, size) == 0);

We know that these are asm labels so it is safe to read up to 'size'
bytes at those addresses.

However, because we have passed the address of a single unsigned int to
memcmp, the compiler believes the underlying object is in fact a single
unsigned int.  So if size > sizeof(unsigned int), there will be a panic
at runtime.

We can fix this by changing the types: instead of calling the asm labels
unsigned ints, call them unsigned int[]s.  Therefore the size isn't
incorrectly determined at compile time and we get a regular unsafe
memcmp and no panic.

[1] http://openwall.com/lists/kernel-hardening/2017/05/09/2

Link: http://lkml.kernel.org/r/1497903987-21002-7-git-send-email-keescook@chromium.org
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Kees Cook <keescook@chromium.org>
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Tested-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

powerpc: don't fortify prom_init

prom_init is a bit special; in theory it should be able to be linked
separately to the kernel.  To keep this from getting too complex, the
symbols that prom_init.c uses are checked.

Fortification adds symbols, and it gets quite messy as it includes
things like panic().  So just don't fortify prom_init.c for now.

Link: http://lkml.kernel.org/r/1497903987-21002-6-git-send-email-keescook@chromium.org
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

IB/rxe: do not copy extra stack memory to skb

This fixes a over-read condition detected by FORTIFY_SOURCE for this
line:

memcpy(SKB_TO_PKT(skb), &ack_pkt, sizeof(skb->cb));

The error was:

  In file included from ./include/linux/bitmap.h:8:0,
                   from ./include/linux/cpumask.h:11,
                   from ./include/linux/mm_types_task.h:13,
                   from ./include/linux/mm_types.h:4,
                   from ./include/linux/kmemcheck.h:4,
                   from ./include/linux/skbuff.h:18,
                   from drivers/infiniband/sw/rxe/rxe_resp.c:34:
  In function 'memcpy',
      inlined from 'send_atomic_ack.constprop' at drivers/infiniband/sw/rxe/rxe_resp.c:998:2,
      inlined from 'acknowledge' at drivers/infiniband/sw/rxe/rxe_resp.c:1026:3,
      inlined from 'rxe_responder' at drivers/infiniband/sw/rxe/rxe_resp.c:1286:10:
  ./include/linux/string.h:309:4: error: call to '__read_overflow2' declared with attribute error: detected read beyond size of object passed as 2nd parameter
      __read_overflow2();

Daniel Micay noted that struct rxe_pkt_info is 32 bytes on 32-bit
architectures, but skb->cb is still 64.  The memcpy() over-reads 32
bytes.  This fixes it by zeroing the unused bytes in skb->cb.

Link: http://lkml.kernel.org/r/1497903987-21002-5-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Moni Shoua <monis@mellanox.com>
Cc: Doug Ledford <dledford@redhat.com>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kexec_file: adjust declaration of kexec_purgatory

Defining kexec_purgatory as a zero-length char array upsets compile time
size checking.  Since this is built on a per-arch basis, define it as an
unsized char array (like is done for other similar things, e.g.  linker
sections).  This silences the warning generated by the future
CONFIG_FORTIFY_SOURCE, which did not like the memcmp() of a "0 byte"
array.  This drops the __weak and uses an extern instead, since both
users define kexec_purgatory.

Link: http://lkml.kernel.org/r/1497903987-21002-4-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

efi: avoid fortify checks in EFI stub

This avoids CONFIG_FORTIFY_SOURCE from being enabled during the EFI stub
build, as adding a panic() implementation may not work well.  This can
be adjusted in the future.

Link: http://lkml.kernel.org/r/1497903987-21002-2-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Suggested-by: Daniel Micay <danielmicay@gmail.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

powerpc/64s: implement arch-specific hardlockup watchdog

Implement an arch-speicfic watchdog rather than use the perf-based
hardlockup detector.

The new watchdog takes the soft-NMI directly, rather than going through
perf.  Perf interrupts are to be made maskable in future, so that would
prevent the perf detector from working in those regions.

Additionally, implement a SMP based detector where all CPUs watch one
another by pinging a shared cpumask.  This is because powerpc Book3S
does not have a true periodic local NMI, but some platforms do implement
a true NMI IPI.

If a CPU is stuck with interrupts hard disabled, the soft-NMI watchdog
does not work, but the SMP watchdog will.  Even on platforms without a
true NMI IPI to get a good trace from the stuck CPU, other CPUs will
notice the lockup sufficiently to report it and panic.

[npiggin@gmail.com: honor watchdog disable at boot/hotplug]
Link: http://lkml.kernel.org/r/20170621001346.5bb337c9@roar.ozlabs.ibm.com
[npiggin@gmail.com: fix false positive warning at CPU unplug]
Link: http://lkml.kernel.org/r/20170630080740.20766-1-npiggin@gmail.com
[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/20170616065715.18390-6-npiggin@gmail.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Don Zickus <dzickus@redhat.com>
Tested-by: Babu Moger <babu.moger@oracle.com> [sparc]
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/watchdog: provide watchdog_nmi_reconfigure() for arch watchdogs

After reconfiguring watchdog sysctls etc., architecture specific
watchdogs may not get all their parameters updated.

watchdog_nmi_reconfigure() can be implemented to pull the new values in
and set the arch NMI watchdog.

[npiggin@gmail.com: add code comments]
Link: http://lkml.kernel.org/r/20170617125933.774d3858@roar.ozlabs.ibm.com
[arnd@arndb.de: hide unused function]
Link: http://lkml.kernel.org/r/20170620204854.966601-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/20170616065715.18390-5-npiggin@gmail.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Don Zickus <dzickus@redhat.com>
Tested-by: Babu Moger <babu.moger@oracle.com> [sparc]
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/watchdog: split up config options

Split SOFTLOCKUP_DETECTOR from LOCKUP_DETECTOR, and split
HARDLOCKUP_DETECTOR_PERF from HARDLOCKUP_DETECTOR.

LOCKUP_DETECTOR implies the general boot, sysctl, and programming
interfaces for the lockup detectors.

An architecture that wants to use a hard lockup detector must define
HAVE_HARDLOCKUP_DETECTOR_PERF or HAVE_HARDLOCKUP_DETECTOR_ARCH.

Alternatively an arch can define HAVE_NMI_WATCHDOG, which provides the
minimum arch_touch_nmi_watchdog, and it otherwise does its own thing and
does not implement the LOCKUP_DETECTOR interfaces.

sparc is unusual in that it has started to implement some of the
interfaces, but not fully yet.  It should probably be converted to a full
HAVE_HARDLOCKUP_DETECTOR_ARCH.

[npiggin@gmail.com: fix]
Link: http://lkml.kernel.org/r/20170617223522.66c0ad88@roar.ozlabs.ibm.com
Link: http://lkml.kernel.org/r/20170616065715.18390-4-npiggin@gmail.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Don Zickus <dzickus@redhat.com>
Reviewed-by: Babu Moger <babu.moger@oracle.com>
Tested-by: Babu Moger <babu.moger@oracle.com> [sparc]
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/watchdog: introduce arch_touch_nmi_watchdog()

For architectures that define HAVE_NMI_WATCHDOG, instead of having them
provide the complete touch_nmi_watchdog() function, just have them
provide arch_touch_nmi_watchdog().

This gives the generic code more flexibility in implementing this
function, and arch implementations don't miss out on touching the
softlockup watchdog or other generic details.

Link: http://lkml.kernel.org/r/20170616065715.18390-3-npiggin@gmail.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Don Zickus <dzickus@redhat.com>
Reviewed-by: Babu Moger <babu.moger@oracle.com>
Tested-by: Babu Moger <babu.moger@oracle.com> [sparc]
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/watchdog: remove unused declaration

Patch series "Improve watchdog config for arch watchdogs", v4.

A series to make the hardlockup watchdog more easily replaceable by arch
code.  The last patch provides some justification for why we want to do
this (existing sparc watchdog is another that could benefit).

This patch (of 5):

Remove unused declaration.

Link: http://lkml.kernel.org/r/20170616065715.18390-2-npiggin@gmail.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Don Zickus <dzickus@redhat.com>
Reviewed-by: Babu Moger <babu.moger@oracle.com>
Tested-by: Babu Moger <babu.moger@oracle.com> [sparc]
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

net/netfilter/x_tables.c: use kvmalloc() in xt_alloc_table_info()

xt_alloc_table_info() basically opencodes kvmalloc() so use the library
function instead.

Link: http://lkml.kernel.org/r/20170531155145.17111-4-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Cc: Florian Westphal <fw@strlen.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc/util.h: update documentation for ipc_getref() and ipc_putref()

Now that ipc_rcu_alloc() and ipc_rcu_free() are removed, document when
it is valid to use ipc_getref() and ipc_putref().

Link: http://lkml.kernel.org/r/20170525185107.12869-21-manfred@colorfullife.com
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc/sem: drop __sem_free()

The remaining users of __sem_free() can simply call kvfree() instead for
better readability.

[manfred@colorfullife.com: Rediff to keep rcu protection for security_sem_alloc()]
Link: http://lkml.kernel.org/r/20170525185107.12869-20-manfred@colorfullife.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc/msg: remove special msg_alloc/free

There is nothing special about the msg_alloc/free routines any more, so
remove them to make code more readable.

[manfred@colorfullife.com: Rediff to keep rcu protection for security_msg_queue_alloc()]
Link: http://lkml.kernel.org/r/20170525185107.12869-19-manfred@colorfullife.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc/shm: remove special shm_alloc/free

There is nothing special about the shm_alloc/free routines any more, so
remove them to make code more readable.

[manfred@colorfullife.com: Rediff, to continue to keep rcu for free calls after a successful security_shm_alloc()]
Link: http://lkml.kernel.org/r/20170525185107.12869-18-manfred@colorfullife.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc: move atomic_set() to where it is needed

Only after ipc_addid() has succeeded will refcounting be used, so move
initialization into ipc_addid() and remove from open-coded *_alloc()
routines.

Link: http://lkml.kernel.org/r/20170525185107.12869-17-manfred@colorfullife.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc/msg.c: avoid ipc_rcu_putref for failed ipc_addid()

Loosely based on a patch from Kees Cook <keescook@chromium.org>:
 - id and retval can be merged
 - if ipc_addid() fails, then use call_rcu() directly.

The difference is that call_rcu is used for failed ipc_addid() calls, to
continue to guaranteed an rcu delay for security_msg_queue_free().

Link: http://lkml.kernel.org/r/20170525185107.12869-16-manfred@colorfullife.com
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc/shm.c: avoid ipc_rcu_putref for failed ipc_addid()

Loosely based on a patch from Kees Cook <keescook@chromium.org>:
 - id and error can be merged
 - if operations before ipc_addid() fail, then use call_rcu() directly.

The difference is that call_rcu is used for failures after
security_shm_alloc(), to continue to guaranteed an rcu delay for
security_sem_free().

Link: http://lkml.kernel.org/r/20170525185107.12869-15-manfred@colorfullife.com
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc/sem.c: avoid ipc_rcu_putref for failed ipc_addid()

Loosely based on a patch from Kees Cook <keescook@chromium.org>:
 - id and retval can be merged
 - if ipc_addid() fails, then use call_rcu() directly.

The difference is that call_rcu is used for failed ipc_addid() calls, to
continue to guaranteed an rcu delay for security_sem_free().

Link: http://lkml.kernel.org/r/20170525185107.12869-14-manfred@colorfullife.com
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc/util: drop ipc_rcu_alloc()

No callers remain for ipc_rcu_alloc().  Drop the function.

[manfred@colorfullife.com: Rediff because the memset was temporarily inside ipc_rcu_free()]
Link: http://lkml.kernel.org/r/20170525185107.12869-13-manfred@colorfullife.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc/msg: avoid ipc_rcu_alloc()

Instead of using ipc_rcu_alloc() which only performs the refcount bump,
open code it.  This also allows for msg_queue structure layout to be
randomized in the future.

Link: http://lkml.kernel.org/r/20170525185107.12869-12-manfred@colorfullife.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc/shm: avoid ipc_rcu_alloc()

Instead of using ipc_rcu_alloc() which only performs the refcount bump,
open code it.  This also allows for shmid_kernel structure layout to be
randomized in the future.

Link: http://lkml.kernel.org/r/20170525185107.12869-11-manfred@colorfullife.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc/sem: avoid ipc_rcu_alloc()

Instead of using ipc_rcu_alloc() which only performs the refcount bump,
open code it to perform better sem-specific checks.  This also allows
for sem_array structure layout to be randomized in the future.

[manfred@colorfullife.com: Rediff, because the memset was temporarily inside ipc_rcu_alloc()]
Link: http://lkml.kernel.org/r/20170525185107.12869-10-manfred@colorfullife.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc/util: drop ipc_rcu_free()

There are no more callers of ipc_rcu_free(), so remove it.

Link: http://lkml.kernel.org/r/20170525185107.12869-9-manfred@colorfullife.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc/msg: do not use ipc_rcu_free()

Avoid using ipc_rcu_free, since it just re-finds the original structure
pointer.  For the pre-list-init failure path, there is no RCU needed,
since it was just allocated.  It can be directly freed.

Link: http://lkml.kernel.org/r/20170525185107.12869-8-manfred@colorfullife.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc/shm: do not use ipc_rcu_free()

Avoid using ipc_rcu_free, since it just re-finds the original structure
pointer.  For the pre-list-init failure path, there is no RCU needed,
since it was just allocated.  It can be directly freed.

Link: http://lkml.kernel.org/r/20170525185107.12869-7-manfred@colorfullife.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc/sem: do not use ipc_rcu_free()

Avoid using ipc_rcu_free, since it just re-finds the original structure
pointer.  For the pre-list-init failure path, there is no RCU needed,
since it was just allocated.  It can be directly freed.

Link: http://lkml.kernel.org/r/20170525185107.12869-6-manfred@colorfullife.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc: drop non-RCU allocation

The only users of ipc_alloc() were ipc_rcu_alloc() and the on-heap
sem_io fall-back memory.  Better to just open-code these to make things
easier to read.

[manfred@colorfullife.com: Rediff due to inclusion of memset() into ipc_rcu_alloc()]
Link: http://lkml.kernel.org/r/20170525185107.12869-5-manfred@colorfullife.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/sem.h: correctly document sem_ctime

sem_ctime is initialized to the semget() time and then updated at every
semctl() that changes the array.

Thus it does not represent the time of the last change.

Especially, semop() calls are only stored in sem_otime, not in
sem_ctime.

This is already described in ipc/sem.c, I just overlooked that there is
a comment in include/linux/sem.h and man semctl(2) as well.

So: Correct wrong comments.

Link: http://lkml.kernel.org/r/20170515171912.6298-4-manfred@colorfullife.com
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: <1vier1@web.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc: merge ipc_rcu and kern_ipc_perm

ipc has two management structures that exist for every id:
 - struct kern_ipc_perm, it contains e.g. the permissions.
 - struct ipc_rcu, it contains the rcu head for rcu handling and the
   refcount.

The patch merges both structures.

As a bonus, we may save one cacheline, because both structures are
cacheline aligned.  In addition, it reduces the number of casts, instead
most codepaths can use container_of.

To simplify code, the ipc_rcu_alloc initializes the allocation to 0.

[manfred@colorfullife.com: really include the memset() into ipc_alloc_rcu()]
Link: http://lkml.kernel.org/r/564f8612-0601-b267-514f-a9f650ec9b32@colorfullife.com
Link: http://lkml.kernel.org/r/20170525185107.12869-3-manfred@colorfullife.com
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc/sem.c: remove sem_base, embed struct sem

sma->sem_base is initialized with

sma->sem_base = (struct sem *) &sma[1];

The current code has four problems:
 - There is an unnecessary pointer dereference - sem_base is not needed.
 - Alignment for struct sem only works by chance.
 - The current code causes false positive for static code analysis.
 - This is a cast between different non-void types, which the future
   randstruct GCC plugin warns on.

And, as bonus, the code size gets smaller:

  Before:
    0 .text         00003770
  After:
    0 .text         0000374e

[manfred@colorfullife.com: s/[0]/[]/, per hch]
Link: http://lkml.kernel.org/r/20170525185107.12869-2-manfred@colorfullife.com
Link: http://lkml.kernel.org/r/20170515171912.6298-2-manfred@colorfullife.com
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: <1vier1@web.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Fabian Frederick <fabf@skynet.be>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fault-inject: support systematic fault injection

Add /proc/self/task/<current-tid>/fail-nth file that allows failing
0-th, 1-st, 2-nd and so on calls systematically.
Excerpt from the added documentation:

 "Write to this file of integer N makes N-th call in the current task
  fail (N is 0-based). Read from this file returns a single char 'Y' or
  'N' that says if the fault setup with a previous write to this file
  was injected or not, and disables the fault if it wasn't yet injected.
  Note that this file enables all types of faults (slab, futex, etc).
  This setting takes precedence over all other generic settings like
  probability, interval, times, etc. But per-capability settings (e.g.
  fail_futex/ignore-private) take precedence over it. This feature is
  intended for systematic testing of faults in a single system call. See
  an example below"

Why add a new setting:
1. Existing settings are global rather than per-task.
   So parallel testing is not possible.
2. attr->interval is close but it depends on attr->count
   which is non reset to 0, so interval does not work as expected.
3. Trying to model this with existing settings requires manipulations
   of all of probability, interval, times, space, task-filter and
   unexposed count and per-task make-it-fail files.
4. Existing settings are per-failure-type, and the set of failure
   types is potentially expanding.
5. make-it-fail can't be changed by unprivileged user and aggressive
   stress testing better be done from an unprivileged user.
   Similarly, this would require opening the debugfs files to the
   unprivileged user, as he would need to reopen at least times file
   (not possible to pre-open before dropping privs).

The proposed interface solves all of the above (see the example).

We want to integrate this into syzkaller fuzzer.  A prototype has found
10 bugs in kernel in first day of usage:

  https://groups.google.com/forum/#!searchin/syzkaller/%22FAULT_INJECTION%22%7Csort:relevance

I've made the current interface work with all types of our sandboxes.
For setuid the secret sauce was prctl(PR_SET_DUMPABLE, 1, 0, 0, 0) to
make /proc entries non-root owned.  So I am fine with the current
version of the code.

[akpm@linux-foundation.org: fix build]
Link: http://lkml.kernel.org/r/20170328130128.101773-1-dvyukov@google.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kcmp: fs/epoll: wrap kcmp code with CONFIG_CHECKPOINT_RESTORE

kcmp syscall is build iif CONFIG_CHECKPOINT_RESTORE is selected, so wrap
appropriate helpers in epoll code with the config to build it
conditionally.

Link: http://lkml.kernel.org/r/20170513083456.GG1881@uranus.lan
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Reported-by: Andrew Morton <akpm@linuxfoundation.org>
Cc: Andrey Vagin <avagin@openvz.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kcmp: add KCMP_EPOLL_TFD mode to compare epoll target files

With current epoll architecture target files are addressed with
file_struct and file descriptor number, where the last is not unique.
Moreover files can be transferred from another process via unix socket,
added into queue and closed then so we won't find this descriptor in the
task fdinfo list.

Thus to checkpoint and restore such processes CRIU needs to find out
where exactly the target file is present to add it into epoll queue.
For this sake one can use kcmp call where some particular target file
from the queue is compared with arbitrary file passed as an argument.

Because epoll target files can have same file descriptor number but
different file_struct a caller should explicitly specify the offset
within.

To test if some particular file is matching entry inside epoll one have
to

 - fill kcmp_epoll_slot structure with epoll file descriptor,
   target file number and target file offset (in case if only
   one target is present then it should be 0)

 - call kcmp as kcmp(pid1, pid2, KCMP_EPOLL_TFD, fd, &kcmp_epoll_slot)
    - the kernel fetch file pointer matching file descriptor @fd of pid1
    - lookups for file struct in epoll queue of pid2 and returns traditional
      0,1,2 result for sorting purpose

Link: http://lkml.kernel.org/r/20170424154423.511592110@gmail.com
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Andrey Vagin <avagin@openvz.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

procfs: fdinfo: extend information about epoll target files

Since it is possbile to have same number in tfd field (say file added,
closed, then nother file dup'ed to same number and added back) it is
imposible to distinguish such target files solely by their numbers.

Strictly speaking regular applications don't need to recognize these
targets at all but for checkpoint/restore sake we need to collect
targets to be able to push them back on restore stage in a proper order.

Thus lets add file position, inode and device number where this target
lays.  This three fields can be used as a primary key for sorting, and
together with kcmp help CRIU can find out an exact file target (from the
whole set of processes being checkpointed).

Link: http://lkml.kernel.org/r/20170424154423.436491881@gmail.com
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Andrei Vagin <avagin@virtuozzo.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kfifo: clean up example to not use page_link

This is a layering violation so we replace the uses with calls to
sg_page().  This is a prep patch for replacing page_link and this is one
of the very few uses outside of scatterlist.h.

Link: http://lkml.kernel.org/r/1495663199-22234-1-git-send-email-logang@deltatee.com
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Stephen Bates <sbates@raithlin.com>
Acked-by: Stefani Seibold <stefani@seibold.net>
Cc: Stefani Seibold <stefani@seibold.net>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/gdb: lx-dmesg: use explicit encoding=utf8 errors=replace

Use errors=replace because it is never desirable for lx-dmesg to fail on
string decoding errors, not even if the log buffer is corrupt and we
show incorrect info.

The kernel will sometimes print utf8, for example the copyright symbol
from jffs2.  In order to make this work specify 'utf8' everywhere
because python2 otherwise defaults to 'ascii'.

In theory the second errors='replace' is not be required because
everything that can be decoded as utf8 should also be encodable back to
utf8.  But it's better to be extra safe here.  It's worth noting that
this is definitely not true for encoding='ascii', unknown characters are
replaced with U+FFFD REPLACEMENT CHARACTER and they fail to encode back
to ascii.

Link: http://lkml.kernel.org/r/acee067f3345954ed41efb77b80eebdc038619c6.1498481469.git.leonard.crestez@nxp.com
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Acked-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Kieran Bingham <kieran@ksquared.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/gdb: lx-dmesg: cast log_buf to void* for addr fetch

In some cases it is possible for the str() conversion here to throw
encoding errors because log_buf might not point to valid ascii.  For
example:

  (gdb) python print str(gdb.parse_and_eval("log_buf"))
  Traceback (most recent call last):
    File "<string>", line 1, in <module>
  UnicodeEncodeError: 'ascii' codec can't encode character u'\u0303' in
   position 24: ordinal not in range(128)

Avoid this by explicitly casting to (void *) inside the gdb expression.

Link: http://lkml.kernel.org/r/ba6f85dbb02ca980ebd0e2399b0649423399b565.1498481469.git.leonard.crestez@nxp.com
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Kieran Bingham <kieran@ksquared.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/gdb: add lx-fdtdump command

lx-fdtdump dumps the flattened device tree passed to the kernel from the
bootloader to the filename specified as the command argument.  If no
argument is provided it defaults to fdtdump.dtb.  This then allows
further post processing on the machine running GDB.  The fdt header is
also also printed in the GDB console.  For example:

  (gdb) lx-fdtdump
  fdt_magic:         0xD00DFEED
  fdt_totalsize:     0xC108
  off_dt_struct:     0x38
  off_dt_strings:    0x3804
  off_mem_rsvmap:    0x28
  version:           17
  last_comp_version: 16
  Dumped fdt to fdtdump.dtb

  >fdtdump fdtdump.dtb | less

This command is useful as the bootloader can often re-write parts of the
device tree, and this can sometimes cause the kernel to not boot.

Link: http://lkml.kernel.org/r/1481280065-5336-2-git-send-email-kbingham@kernel.org
Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Kieran Bingham <kbingham@kernel.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/Kconfig: kill CONFIG_PERCPU_RWSEM some more

As of commit bf3eac84c42d ("percpu-rwsem: kill CONFIG_PERCPU_RWSEM") we
unconditionally build pcpu-rwsems.  Remove a leftover in for
FILE_LOCKING.

Link: http://lkml.kernel.org/r/20170518180115.2794-1-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

bfs: fix sanity checks for empty files

Mount fails if file system image has empty files because of sanity check
while reading superblock.  For empty files disk offset to end of file
(i_eoffset) is cpu_to_le32(-1).  Sanity check comparison, which compares
disk offset with file system size isn't valid for this value and hence
is ignored with this patch.

Steps to reproduce:

  $  dd if=/dev/zero of=bfs-image count=204800
  $  mkfs.bfs bfs-image
  $  mkdir bfs-mount-point
  $  sudo mount -t bfs -o loop bfs-image bfs-mount-point/
  $  cd bfs-mount-point/
  $  sudo touch a
  $  cd ..
  $  sudo umount bfs-mount-point/
  $  sudo mount -t bfs -o loop bfs-image bfs-mount-point/
  mount: /dev/loop0: can't read superblock

  $  dmesg
  [25526.689580] BFS-fs: bfs_fill_super(): Inode 0x00000003 corrupted

Tigran said:
 "If you had created the filesystem with the proper mkfs under SCO
  UnixWare 7 you (probably) wouldn't encounter this issue. But since
  commercial Unix-es are now part of history and the only proper way is
  the Linux mkfs.bfs utility, your patch is fine"

Link: http://lkml.kernel.org/r/20170505201625.GA3097@hercules.tuxera.com
Signed-off-by: Rakesh Pandit <rakesh@tuxera.com>
Acked-by: Tigran Aivazian <aivazian.tigran@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

random: do not ignore early device randomness

The add_device_randomness() function would ignore incoming bytes if the
crng wasn't ready.  This additionally makes sure to make an early enough
call to add_latent_entropy() to influence the initial stack canary,
which is especially important on non-x86 systems where it stays the same
through the life of the boot.

Link: http://lkml.kernel.org/r/20170626233038.GA48751@beast
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Lokesh Vutla <lokeshvutla@ti.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/sysctl_binary.c: check name array length in deprecated_sysctl_warning()

Prevent use of uninitialized memory (originating from the stack frame of
do_sysctl()) by verifying that the name array is filled with sufficient
input data before comparing its specific entries with integer constants.

Through timing measurement or analyzing the kernel debug logs, a
user-mode program could potentially infer the results of comparisons
against the uninitialized memory, and acquire some (very limited)
information about the state of the kernel stack.  The change also
eliminates possible future warnings by tools such as KMSAN and other
code checkers / instrumentations.

Link: http://lkml.kernel.org/r/20170524122139.21333-1-mjurczyk@google.com
Signed-off-by: Mateusz Jurczyk <mjurczyk@google.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Matthew Whitehead <tedheadster@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

test_sysctl: test against int proc_dointvec() array support

Add a few initial respective tests for an array:

  o Echoing values separated by spaces works
  o Echoing only first elements will set first elements
  o Confirm PAGE_SIZE limit still applies even if an array is used

Link: http://lkml.kernel.org/r/20170630224431.17374-7-mcgrof@kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

test_sysctl: add simple proc_douintvec() case

Test against a simple proc_douintvec() case.  While at it, add a test
against UINT_MAX.  Make sure UINT_MAX works, and UINT_MAX+1 will fail
and that negative values are not accepted.

Link: http://lkml.kernel.org/r/20170630224431.17374-6-mcgrof@kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

test_sysctl: add simple proc_dointvec() case

Test against a simple proc_dointvec() case.  While at it, add a test
against INT_MAX.  Make sure INT_MAX works, and INT_MAX+1 will fail.
Also test negative values work.

Link: http://lkml.kernel.org/r/20170630224431.17374-5-mcgrof@kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

test_sysctl: test against PAGE_SIZE for int

Add the following tests to ensure we do not regress:

  o Test using a buffer full of space (PAGE_SIZE-1) followed by a
    single digit works

  o Test using a buffer full of spaces (PAGE_SIZE or over) will fail

As tests increase instead of unloading the module and reloading it we
can just do a shell reset_vals() with a reset to values we know are set
at init on the driver.

Link: http://lkml.kernel.org/r/20170630224431.17374-4-mcgrof@kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>